If you're going to print ABS inside a heated chamber, water cooling the extruder makes sense because the ambient air temperature may not be low enough to prevent heat creep up the throat of the extruder. I print ABS in a 45-50C enclosure using air cooling and it works, but maybe the OP is planning on a warmer temperature. Stratasys prints ABS inside a 70C oven.
Or like he said, the extruder is too small for air cooling...
Edited 1 time(s). Last edit at 07/24/2016 06:47AM by the_digital_dentist.
Ultra MegaMax Dominator 3D printer: [
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